This invention relates to a coupling for joining an ostomy bag to a pad or surgical dressing. Ostomy bags are usually secured to a pad or surgical dressing which contacts the user's skin and surrounds the stoma. The term `ostomy bag` is intended to include colostomy, ileostomy, urostomy and other bags used for example after surgical intervention procedures. There is a need for a coupling between pad and bag which allows the bag to be readily removed when necessary, and replaced by a clean, empty bag, At the same time, it is essential that the coupling should be a secure one, and prevent leakage particularly of liquids and gases.
Efforts were made some time ago, see for example the proposal in British Patent Specification No. 1 021 145 published in 1966, to provide a connector whereby the bag can be readily removed and replaced. But this arrangement involves two separate operations, unscrewing and then removal. That is, first one must unscrew the connector which carries the bag from the connector which is secured to the body and this involves a risk of leakage as it is necessary to invert the bag. Also it is an awkward operation. It will be appreciated that at this time the bag is full or partly full of bodily waste products, and manipulation of the coupling will be an unpleasant operation even if, as is often not the case, the user has a high degree of dexterity.
British Patent Specification No. 1 099 455 discloses an appliance in which one ring co-operates with a second part-ring which is used to trap the neck of a bag when the two rings are inter-engaged with the bag mouth between them. If adequate security against leakage is to be provided, it is necessary that the two rings should be a tight fit; however, this makes it difficult for the user to pull off the part-ring. As th part-ring is pulled off, there is the probability that the security of attachment of the first ring to the surgical dressing, or of the dressing to the skin of the wearer, will be impaired. This may also cause discomfort to the wearer.
A more recent and commercially successful proposal is described and claimed in British Patent No. 1 571 657. While the ostomy bag coupling according to Patent No. 1 571 657 has enjoyed wide user acceptability, the search for a simpler coupling which at the same time is of flatter design has continued. It will be understood that a flatter design is desirable in order that the bag when worn under clothes should be unobtrusive.
An ostomy coupling is shown in U.K. Patent Application No. 2 153 683(J. V. Edwards). This adopts the known concept of a deflectible seal strip and relies on a single strip of plastics to serve a sealing function between two connected coupling rings; in addition the seal strip is involved in transmitting to the body side coupling substantially all of the downward forces arising from the weight of the bag and its contents. In this design, the load applied to the seal strip may well cause its effectiveness as a seal to deteriorate. This application also shows a rotatable ring for attachment of a belt. The present Applicant is unaware of any current commercial utilization of the device shown in the Edwards application.